PGA112 Gain Amplifier Texas Instruments' PGA112 single-supply, single-ended, precision programmable gain amplifer provides integrated front-end programmable gain amplification for microcontroller based systems with on-board A to D converters and D to A converters. Programmable gains allow matching of sensor output to an ADC input voltage range and internal calibration channels are provided for system-level calibration. The device has a two channel input mulitplexer to allow inputs from multiple sources, a standard SPI serial interface, and software shutdown that reduces quiescent current to <,4µA. The PGA112 not only solves the problem of finding matched discrete components, but it includes the benefits of 2-channels, calibration, and digitally controlled gain.